The present application relates to thermal management and, more particularly, to micro-scale cooling devices that generate ions and electrical fields to motivate flow of fluids, such as air, as part of a thermal management solution to dissipate heat.
Many devices or systems, whether electronic, optical, mechanical, may include, provide or require forced flow of air or some other fluid. In some cases, the forced flow is useful to cool or otherwise moderate heat evolved by thermal sources within the device or system. In such cases, cooling or thermal moderation may help prevent device overheating, reduce thermal hotspots, provide desired thermal stability for temperature sensitive devices, improve long term reliability or provide other benefits. In some cases, forced flow may be a primary function of the device or system.
It is known in the art to provide cooling air flow using fans, blowers or other similar moving mechanical devices; however, such devices generally have limited operating lifetimes, tend to produce undesired noise or vibration, consume power or suffer from other design problems. In addition, such devices can often impose constraints of geometry, form factor and/or layout in systems for which they provide cooling air flows. These constraints can be particularly problematic in modern consumer electronics devices for which size has become an important market differentiator.
In general, electrohydrodynamic (EHD) technology uses ion flow principles to move fluids (e.g., air molecules). Devices built using the principle of ionic movement of a fluid are variously referred to in the literature as ionic wind machines, electric wind machines, corona wind pumps, electro-fluid-dynamics (EFD) devices, electrostatic fluid accelerators (EFAs), electrohydrodynamic (EHD) thrusters and EHD gas pumps. Some aspects of the technology have also been exploited in devices referred to as electrostatic air cleaners or electrostatic precipitators.
In some applications, the use of an ion flow air mover device, such as an EHD device or EFD device, may result in improved cooling efficiency and reduced vibrations, power consumption, electronic device temperatures, and noise generation. In such deployments, an EHD device may reduce costs, allow for reduced device size, thickness or volume, and may in some cases improve electronic device performance and/or user experience.
Accordingly, improvements are sought in implementing EHD air mover cooling in traditionally mechanical fan-cooled applications.